At present, many families have more than one computing device, such as a desktop computer, a notebook computer, a tablet computer, smart phone and so on. Each of these computing devices may have its own graphics card or subsystem. Usually, people use their computing devices at home to edit texts, receive and send e-mails, enjoy music and so on. But sometimes, there may be some special needs, for example, running video-processing software on the computing device. In that case, the graphics card of the computing device is expected to ramp up to deal with complex and heavy load image processing. Obviously, it is not economical and necessary to replace the graphics card with a more powerful one for this computing device for such a temporary need. And there may be other computing devices at home which are in idle states, which is a waste of resources.